In the scope of practical application of the invention, i.e., that of the panels used for forming self-supporting air-conditioning ducts, the ducts preferably embodied in mineral wool, are well known, wherein the panels forming the duct are coupled in a tongue-and-groove manner establishing a canted edge in said coupling.
Theoretically, the coupling in a tongue-and-groove manner is carried out by means of perpendicular cuts between the two panels to be joined, which perpendicular cuts have been made relative to the longitudinal line of the panels' intersection.
Nevertheless, in reality, there are problems with the tongue-and-groove adjustment, caused by the curvatures resulting from the molding process, which make the surface to have cavities and irregularities at the joints of the different modules of the final duct.
With the aim of solving this problem, the applicant himself is the holder of the utility model U201100838, in which a coupling in a tongue-and-groove manner between this type of panels is described, wherein the coupling and juxtaposing canted edged or edge of both panels, has an oblique cut relative to the horizontality or the longitudinal intermediate line in the joint between the two panels.
While this structure achieves a much effective inter-modules coupling, this solution poses a problem, i.e., given the coupling arrangement, it is possible that particles from the mineral wool core of the panel get detached in the event of mechanical cleaning or maintenance operations, falling towards the inside of the duct and being swept by the air flow.